The present invention is directed to implantable pumps, pump systems and methods of use. A particular use of the present invention is described for pumping blood; however, the invention may be used for any other purpose without departing from the scope of the invention. For example, the pump may be used for drug infusion or as a spinal fluid pump.
Conventional implantable blood pumps often include a pumping element having magnets attached thereto. The magnets are driven by magnetic forces produced by coils positioned around the pumping element. A battery powers the coils. The battery can be recharged from an external source using a transcutaneous energy transfer (TET) system having external TET coils and internal TET coils. An electrical current is directed through the external TET coils to produce a magnetic field, which impinges on the internal TET coils thereby inducing electrical power generation at the internal coils for charging the battery.
The present invention is directed to improved methods, systems and devices related to implantable pumps.
In a first aspect of the invention, the pump system has an external driver, which drives the pumping element, such as an impeller, with a direct magnetic coupling. The external driver may be static coils which are charged appropriately or rotating magnets. A battery may also be provided which supplies power to run the pumping element when the external driver is not being used. The external driver provides the ability for emergency operation of the pump if the battery, or some other part of the electrical system, should fail.
In another aspect of the present invention, the battery is recharged by generating electricity from the mechanical energy of the pumping element. The energy is preferably generated at the internal coils, which drive the pumping element when the battery is being used. Use of the internal coils for generating energy to power the battery obviates the need to provide an independent set of internal TET coils as is required in many prior art systems as described above.
The present invention is also directed to methods of pumping blood in a patient. In particular, the present invention is directed to methods of providing partial circulatory support. In another aspect of the present invention, the pump is preferably implanted at a subpectoral location outside the patient""s ribs. This location for the pump may be less traumatic to surgically implant than a pump mounted within the chest. The battery may be implanted subpectorally and outside the patient""s ribs on the other side of the patient""s chest.
The present invention is also directed to methods for pumping blood in a patient. A blood pump having a pumping element, a blood inlet, a blood inlet lumen and a blood outlet is implanted into a patient. The blood inlet is coupled to a first vascular location with the blood inlet lumen extending through the right atrium, through the atrial septum and into the left atrium. The blood inlet may be coupled to any suitable vessel such as a femoral or subclavian vein. The blood outlet may also be coupled to any suitable vessel such as the femoral or subclavian arteries.
These and other aspects of the present invention will become apparent from the description of the preferred embodiment.